No going to set here and way crafting isn't a grind, but I will say I can craft implants and medpacs on my main for alts better than anything that will drop in flashpoints while leveling. However, to get to that point it was a grind. I had to craft an RE over and over to go from greens, to blues to purples.
If I only had one slot, leveling I think slicing would be my pick too. Very easy credit with slicing. However, after 50 and augmented, then biochem would be my pick for reuseable, medpacs, stims and adrenals. However, as long people need augments, they need mats, so slicing will continue to make credits.